Supercritical fluid chromatography for the analysis of natural dyes: From carotenoids to flavonoids.

Plant-derived natural dyes are used in a variety of formulated products, from food to cosmetics and pharmaceutics. In addition to their color, they also provide some bioactivity. While they are mostly analyzed with high-performance liquid chromatography, supercritical fluid chromatography was also employed for several dye families, mostly for carotenoids and chlorophylls, and more recently for anthraquinones and flavonoids. These supercritical fluid chromatography methods are described in this review. Because the dyes have different structures and structural variations (polarity, isomers, etc.), the best chromatographic system to achieve their separation is not always the same. Hydrophobic stationary phases are preferred for the most hydrophobic dyes (chlorophylls and carotenoids) while polar stationary phases are preferred for the polar dyes (anthraquinones and flavonoids). Regarding the mobile phase composition, chlorophylls and carotenoids are best eluted with moderate proportions of co-solvent in CO2 (about 40%), while the most polar glycosylated flavonoids require higher proportions of co-solvent and acidic additives. Because dyes are colorful, ultraviolet-visible detection is often sufficient, while mass spectrometry offers additional structural information. Furthermore, fundamental information can also be gained through chromatographic analysis of dyes: either solubility in supercritical fluids, in view of their extraction, or retention behavior providing an understanding of stationary phase properties.

A Study On the Optoelectronic Parameters of Natural Dyes Extracted from Beetroot, Cabbage, Walnut, and Henna for Potential Applications in Organic Electronics.

In this work, the optoelectronic parameters of natural dyes extracted from beetroot, red cabbage, walnut leaves, and henna were comprehensively investigated, namely the optical energy gap (Eg), extinction coefficient (k), refractive index (n), dielectric constant ([Formula: see text], and optical conductivity ([Formula: see text]. Results showed a high refractive index, dielectric constant and optical conductivity ([Formula: see text] and [Formula: see text]) for the dye extracted from red cabbage, while minimum values of [Formula: see text] and [Formula: see text] were obtained for the henna dye. The transition type of the optical absorption of the dyes was found to be a direct allowed transition, which is taken place between the bonding and antibonding molecular energy levels. The reported results herein are essential in revealing the viability of these natural dyes for potential applications in organic electronics, including organic photovoltaics, photodiodes, and sensors.

Copaifera langsdorffii Desf. bark extract: optimisation of dyeing conditions to wool and colour fastness properties.

The ability to add value to waste materials from industrial operations has come to the attention of the wood processing industry, with reports, for example, of extracts from the bark tree conveying colour and UV protection to textile fibres. The objective of the present work was to expand our developments in this arena by using Copaifera langsdorffii Desf. bark extract as a natural dye for textile dyeing. A complete 2³-statistical experimental design and the central point was elaborated. The results showed that the optimal dyeing conditions were 98 °C, for 60 min, using undiluted bark extract. The dyed fabric was analysed by a spectrophotometer using the CIELAB system for evaluation of the colour strength. The results showed a K/S value of 5.78, and the dyed fabric had good colour fastness to rubbing and washing.

Anthocyanins from purple passion fruit (Passiflora edulia Sims) rind-An innovative source for nonbleachable pigment production.

Passion fruit rind is a waste product from the beverage industry that is rich in anthocyanins that can be potentially applied as a natural colorant. However, the inherent instability of anthocyanins causes rapid discoloration. In this study, the cyanidin-3-glucoside (C-3-G) in passion fruit rind was extracted using 50% ethanol and converted into nonbleachable pigments by reaction with Oolong tea extracts and acetaldehyde. Reactions over 70 days formed high concentrations of stable nonbleachable pigments (3.07-6.68 absorbance unit [A.U.], in total) such as pyranoanthocyanins, as well as oligomeric and polymeric pigments with ethyl-linked bridges. In C-3-G and acetaldehyde reaction, positive relations were found among acetaldehyde concentration, color density, and nonbleachable pigment concentrations. As for reactions with C-3-G and Oolong tea extract combined with acetaldehyde, greater color density and greater concentrations of nonbleachable pigments (10.80-12.34, 4.25-4.40 A.U., respectively) were formed compared with acetaldehyde alone. In addition, the antioxidant capabilities of the extracts were enhanced after reaction with Oolong tea extracts. The results of this study show a useful method to enhance the stability of anthocyanins from passion fruit rind and also provide greater economic value to this waste product. PRACTICAL APPLICATION: Ripened passion fruits contain a high concentration of anthocyanins in their rind. These anthocyanins can be optimally extracted by ultrasonic assisted solvent extraction to provide stable pigments by inducing acetaldehyde (a volatile compound often found in foods and beverages) into the anthocyanins. These stable pigments have a greater reddish hue in solution than the anthocyanin extracted from the rind and are more stable over a greater pH range. In addition, these stable pigments can be potentially used as colorant throughout the food and cosmetic industry to provide high economical values.

TiO2@HNTs Robustly Decorated PVDF Membrane Prepared by a Bioinspired Accurate-Deposition Strategy for Complex Corrosive Wastewater Treatment.

As industrialization has spread all around the world, the problems of water pollution such as offshore oil spill and industrial sewage discharge have spread with it. Although many new separation materials have been successfully developed to deal with this crisis, a large number of water treatment materials only focus on the treatment of classified single water pollutant under mild conditions. It is a great challenge to treat soluble contaminants such as water-soluble dyes and insoluble contaminants, for example, emulsified oils simultaneously in a strong corrosive environment. Herein, in this work, corrosive resistance and multifunctional surface on a commercial polyvinylidene difluoride (PVDF) membrane via a tunicate-inspired gallic acid-assisted accurate-deposition strategy is created. Owing to the titanium-carboxylic coordination bonding and accurate-deposition strategy, the as-prepared membrane exhibits extraordinary stability, facing various harsh environmental challenges and incredibly corrosive situations (e.g., 4 M NaOH, 4 M HCl, and saturated NaCl solution). The robust multifunctional surface also endows commercial PVDF membrane with the ability for in situ separation and adsorption of surfactant-stabilized oil-in-water (corrosive and dyed) emulsions with high adsorption efficiencies up to 99.9%, separation efficiencies above 99.6%, and permeation flux as high as 15,698 ± 211 L/(m2·h·bar). Furthermore, the resultant membrane can be regenerated facilely and rapidly by flushing a small amount of HCl (4 M) or NaOH (4 M), making the corrosive resistance membrane attain a long-term and high-efficiency application for complex dyed wastewater treatment. Therefore, the multifunctional membrane has a broad application prospect in the industrial field.

Colored Corn: An Up-Date on Metabolites Extraction, Health Implication, and Potential Use.

Colored (orange, pink, red, purple, and blue) corn strongly attracted attention on its healthy properties mainly due to its anthocyanin and carotenoid composition which is also responsible for its pigmentation. The present review summarized the recent updates on the extraction and chemical characterization of the main plant secondary metabolites present in colored seeds, kernel, cob, husk, and silk. The main approaches used to stabilize the extracts have been discussed as well as their food and non-food uses. Both in vitro and in vivo (animal models) studies on the different effects (antibacterial, antimutagenic, antioxidant, and anti-inflammatory activities, effects on metabolic syndrome, diabetes, glucose and lipidic metabolism, and neuroprotection) of pigmented extracts on animal and human health have been summarized.

Application of Natural Pigments in Ordinary Cooked Ham.

The possibility of obtaining a carmine or pink color on ordinary cooked ham by applying natural dyes from three plant species, namely red radish (Raphanus sativus L.), hibiscus (Roselle sabdariffa L.) and red beetroot (Beta vulgaris L.), was investigated. The extracts were evaluated for the stability at physical-chemical parameters and subjected to cytotoxicity assays in the gastric cell line AGS Encapsulation of the extracts in soybean lecithin liposomes and maltodextrin microcapsules was performed. Lyophilized extracts before and after encapsulation in maltodextrin were applied in the formulation of ordinary cooked ham and used in a pilot scale of production. The color of cooked ham samples from different assays was evaluated visually and by colorimetry. The results suggest that the coloration of ordinary cooked ham obtained with extracts of red beetroot is very promising for future applications in this type of meat product.

Magnetite nanoparticle embedded Pectin-graft-poly(N-hydroxyethylacrylamide) hydrogel: Evaluation as adsorbent for dyes and heavy metal ions from waste water.

A pectin (Pec) based gel has been made by grafting N-hydroxyethylacrylamide (HEAA) on pectin using potassium peroxodisulphate as initiator and N,N-methylenebisacrylamide as crosslinker under microwave irradiation. The magnetite (Fe3O4) nanoparticles were incorporated within this gel via in situ diffusion of Fe2+ and Fe3+ followed by reaction with ammonia solution. The synthesized gel, pectin-graft-poly(N-hydroxyethylacrylamide) (Pec-g-PHEAA); and the magnetite containing composite (Pec-g-PHEAA/Fe3O4) were characterized by FTIR, TGA, XRD, BET and SEM techniques. The magnetic property measurement indicated ferromagnetic nature of the nanocomposite. The Pec-g-PHEAA and Pec-g-PHEAA/Fe3O4 systems were evaluated for removal of dye and metal ions from aqueous solution using Rhodamine 6G (R6G), a cationic dye; Cu(II) and Hg(II) ions. Both adsorbents showed significant adsorption capacity towards these species, with greater adsorption capacity in case of Pec-g-PHEAA/Fe3O4. Adsorption process is observed to follow both Langmuir and Freundlich isotherm models for R6G dye and Freundlich isotherm model for Cu(II) and Hg(II) ions. The adsorption was found to be a pseudo first order process for R6G and pseudo second order process for Cu(II) and Hg(II) ions. The positive values of ∆H0 and the negative values of ∆G0 indicated the adsorption process to be endothermic and spontaneous.

Interfacial separation of concentrated dye mixtures from solution with environmentally compatible nitrogenous-silane nanoparticles modified with Helianthus annuus husk extract.

The capacity of an adsorbent to bind and remove dye from solution greatly depends on the type of functionalization present on the nanoparticles surface, and its interaction with the dye molecules. Within this study, nitrogenous silane nanoparticles were hydrothermally synthesized resulting in the formation of rapid and highly efficient adsorbents for concentrated mixed dyes. The amorphous silane nanoparticles exhibited a monolayer based mechanism of mixed dye adsorption with removal capacities between 416.67 and 714.29 mg/g of adsorbent. Dye removal was predominantly due to the electrostatic attraction between the positively charged silane nanoparticles (13.22-8.20 mV) and the negatively charged dye molecules (-54.23 mV). Addition of H. annuus extract during synthesis resulted in three times the surface area and 10 times increased pore volume compared to the positive control. XPS analysis showed that silane treatments had various nitrogen containing functionalities at their surface responsible for binding dye. The weak colloidal stability of silane particles (13.22-8.20 mV) was disrupted following dye binding, resulting in their rapid coagulation and flocculation which facilitated the separation of bound dye molecules from solution. The suitability for environmental applications using these treatments was supported by a bacterial viability assay showing >90% cell viability in treated dye supernatants.

Fluorescence quantum yield of natural dye extracted from Tradescantia pallida purpurea as a function of the seasons: Preliminary bioapplication as a fungicide probe for necrotrophic fungi.

In this work, over the course of four seasons (12 months), we have monitored the fluorescence quantum efficiency (η) from two sets (S1 and S2) of fresh natural dye extracts from the leaves of Tradescantia pallida purpurea. The natural dye was extracted in aqueous solutions from leaves collected from regions with a predominance of shade (S1) and sun (S2) during the day. The thermo-optical parameter fractional thermal load (φ) was measured using conical diffraction (CD) patterns caused by thermally driven self-phase modulation, for η determination in both sets of solutions. Fluorescence measurements corroborate the CD results, and the η values are, on average, slightly higher (~ 11%) in the summer than in the other seasons for both sets of samples (S1 and S2). In addition, the experimental results are presented using natural dye extracted from Tradescantia pallida purpurea as a fungicide probe in Fusarium solani, Sclerotinia sclerotiorum, and Colletotrichum gloeosporioides fungi. The promising fungicide results obtained for the aqueous natural dye extract were compared with those obtained for other natural dyes and fungi. The fungi tested are of the necrotrophic group and constitute important pathosystems in Brazil, causing diseases in several crops that synthetic fungicides often cannot control or do so with low efficiency.

Betanin assisted synthesis of betanin@silver nanoparticles and their enhanced adsorption and biological activities.

Natural red purple dye, Betanin, was extracted from the beetroot, purified by aqueous two- phase extraction and gel permeation column chromatography, and used as a reducing agent for the synthesis of silver-betanin core-shell triangular nanodisks for the first time. Spectroscopic data show that the nanoparticle structure is core@shell like with Ag as core and betanin as shell. Langmuir monolayer model (qm = 32.4 mg/g, RL = 0.99 and R2 = 0.997) was the best fit adsorption isotherm for the dye removal. Adsorption kinetics is well explained by pseudo-second-order equation. Gibbs free energy (ΔG0 = -2.59 kJ mol-1), enthalpy (ΔH0 = 18.05 kJ mol-1), and entropy (ΔS0 = 68.92 J/K/mol) were calculated and discussed. The antibacterial activity of betanin-AgNPs were determined against Escherichia coli MTCC-450 (E. coli) and Staphylococcus aureus MTCC-3160 (S. aureus) bacteria.

Biosynthesis of reusable and recyclable CuO@Magnetite@Hen Bone NCs and its antioxidant and antibacterial activities: a highly stable magnetically nanocatalyst for excellent reduction of organic dyes and adsorption of polycyclic aromatic hydrocarbons.

For the first time, through a fast, eco-friendly and economic method, the aqueous extract of the leaf of Euphorbia corollate was used to the green synthesis of the highly stable CuO@Magnetite@Hen Bone nanocomposites (NCs) as a potent antioxidant and antibacterial agent against Pseudomonas aureus, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae pathogenic bacteria. The biosynthesised NCs were identified using the scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, elemental mapping, X-ray diffraction (XRD), Fourier transforms infrared spectroscopy and UV-vis analytical techniques. Also, the radical scavenging activity using (2,2-diphenyl-1-picrylhydrazyl) method was used to evaluate the antioxidant activity of the NCs. The stability of nanocatalyst was monitored using the XRD and SEM analyses after 30 days from its synthesis. Furthermore, its excellent catalytic activity, recycling stability, and high substrate applicability were demonstrated to the adsorption of the polycyclic aromatic hydrocarbons of the light crude oil from Shiwashok oil fields and destruction of methylene blue and methyl orange as harmful organic dyes at ambient temperature using UV-vis spectroscopy. Moreover, the green CuO@Magnetite@Hen Bone NCs were recovered and reused several times without considerable loss of its catalytic activity.

Antibacterial and dye degradation potential of zero-valent silver nanoparticles synthesised using the leaf extract of Spondias dulcis.

The present study reports a simple and low cost synthesis of zero-valent silver nanoparticles (ZVSNPs) from silver nitrate using the leaf extract of Spondias dulcis. The ZVSNPs showed a unique peak at 420 nm in UV-vis spectrum. The SEM image portrayed cuboidal shaped particles. The EDX spectrum designated the elemental silver peak at 3 keV. In XRD, a sharp peak at 32.47° denoted the existence of (1 0 1) lattice plane and the average crystallite size was calculated as 48.61 nm. The lattice parameter was determined as 0.39 nm. The FTIR spectra of the leaf extract and ZVSNPs showed shifts in the specific functional group bands which ascertained the involvement of phytoconstituents in the formation and capping of nanoparticles. The average hydrodynamic size was measured as 59.66 nm by DLS method. A low PDI, 0.187 witnessed the monodispersity. A negative zeta potential value of -15.7 mV indicated the negative surface charges of the nanoparticles. The bactericidal action of ZVSNPs was demonstrated against two pathogens S.typhimurium and E.coli during which a dosage dependent zone of inhibition results was observed. Additionally, the catalytic potential of ZVSNPs was examined for the degradation of methylene blue dye in which an accelerated degradation of the dye was observed.

Poly(deep eutectic solvent)-functionalized magnetic metal-organic framework composites coupled with solid-phase extraction for the selective separation of cationic dyes.

Novel polymeric deep eutectic solvents (PDES) based on 3-acrylamidopropyl trimethylammonium chloride/D-sorbitol functionalized amino-magnetic (Fe3O4NH2) metal-organic framework (HKUST-1-MOF) composites (Fe3O4NH2@HKUST-1@PDES) were synthesized and characterized by field emission transmission electron microscope (FE-SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), fourier transform infrared spectrometry (FT-IR), thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM) and zeta potentials. Then the composites were firstly utilized to selectively separate malachite green (MG) and crystal violet (CV) coupled with magnetic solid-phase extraction (MSPE). A response surface methodology (RSM) based on Latin hypercube sampling (LHS) was selected to analytically optimize the extraction parameters including initial concentration of dyes, extraction time, pH value and extraction temperature. The maximum extraction amount and optimal extraction conditions predicted by the RSM model matched well with the actual experimental results, and the extraction amount was 966.93 mg g-1 for MG and 788.90 mg g-1 for CV,respectively. The results indicated that the model possessed higher calculation accuracy through analyzing fewer sample points, thereby achieving theoretical prediction of extraction amount and conditions and being a prefect supplementary to actual experiments. The electrostatic interaction between the composites and cationic dyes played the main roll in the extraction process. The proposed extraction method exhibited lower limit of detection (98.19 ng mL-1 for MG and 23.97 ng mL-1 for CV) and preeminent precision (RSD ˂ 0.4%). Spiked recoveries of fish samples at three spiking levers ranged from 89.43% to 100.65% for MG and 95.29%-98.03% for CV. All results highlighted the excellent potential of Fe3O4NH2@HKUST-1@PDES-MSPE strategy in selective separation of cationic dyes in complex medium.

Evaluation of an extract of the Punica granatum flower as a biological stain of rat tissues: a preliminary study.

Natural dyes and especially hematoxylin, which is herbal, are widely used in staining tissues. The aim of this study is to evaluate the staining status of different tissues taken from rats with pomegranate flower extract. For this reason, 2 Wistar albino rats, one male and one female, were used as stain biomaterial. A histological follow up procedure was applied to the lung, kidney, liver, and heart tissue samples taken from the rats and the unstained preparates of these tissues were prepared. As the source of the dye, the dry flowers of Punica granatum (PG) obtained from local markets of Kayseri were used. Each tissue sample underwent the same staining procedure with the same temperature, duration, and dye solution. Before and after the staining procedure, × 40 images of the tissue preparates were taken using a light microscope. Generally, different tones of staining were observed in the nuclei and cytoplasms of all cells and epithelium cells. Staining in parts specific to each tissue occurred. For example, there were light stains on the glomerular cells and the Bowman capsule in the kidney tissue Differences in staining can only be explained by molecular diversity differences in tissue. However, in order to improve the initial staining results obtained in this study, it is possible that working with different temperatures, pH values, mordant substances, and dye that the dye molecules in the extract will provide more vivid colors with different molecules in the tissues.

Dyeing wool and cotton fibres with acidic extract of Hibiscus rosa sinensis flower.

The focus of this work is to extract a natural dye for colouring camel wool as a substitute for synthetic dyes used in the Sadu House of Kuwait. Their target is to keep the tradition of tent and rug production natural in all its manifestations. Therefore, our task was to find an abundant source that provides a colour preferably red to purple. Hibiscus rosa sinensis (HRS) is an abundantly available plant in Kuwait that was explored for extraction of the red dye to colour camel wool permanently. The powdered petals of red flowers of HRS was extracted with 5% acetic acid which yielded a deep red colour that showed a great potential for woollen fibre dyeing. The use of mordants like alum and some metal salts manifested a wide range of fixed colours which intensified at 85 °C. The colours produced had excellent fastness and was accepted by the Sadu House.

UHPLC Analysis of Saffron (Crocus sativus L.): Optimization of Separation Using Chemometrics and Detection of Minor Crocetin Esters.

Ultra-high performance liquid chromatography (UHPLC) coupled with diode array detection (DAD) was applied to improve separation and detection of mono- and bis-glucosyl esters of crocetin (crocins), the main red-colored constituents of saffron (Crocus sativus L.), and other polar components. Response surface methodology (RSM) was used to optimise the chromatographic resolution on the Kinetex C18 (Phenomenex) column taking into account of the combined effect of the column temperature, the eluent flow rate and the slope of a linear eluent concentration gradient. A three-level full-factorial design of experiments was adopted to identify suitable combinations of the above factors. The influence of the separation conditions on the resolutions of 22 adjacent peaks was simultaneously modelled by a multi-layer artificial neural network (ANN) in which a bit string representation was used to identify the target analytes. The chromatogram collected under the optimal separation conditions revealed a higher number of crocetin esters than those already characterised by means of mass-spectrometry data and usually detected by HPLC. Ultra-high performance liquid chromatography analyses carried out on the novel Luna Omega Polar C18 (Phenomenex) column confirmed the large number of crocetin derivatives. Further work is in progress to acquire mass-spectrometry data and to clarify the chemical structure to the newly found saffron components.

Green reduction of graphene oxide using eucalyptus leaf extract and its application to remove dye.

Reduction of graphene oxide (RGO) utilizing green methods such as plants has attracted much attention due to its efficiency, eco-friendly features and low cost. However, the key components in plant extracts and their bioreduction functions concerning GO are still not well understood. In this study, the GO was reduced by Eucalyptus leaf (EL) extract. The optimal conditions for bioreduction were at volume ratio of leaf extract (10 g L-1) and GO (0.5 g L-1) solution of 1:4 for 8 h at 80 °C. The RGO was characterized with Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), transmission electron microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FTIR). Results confirmed the oxygen-containing groups in GO were efficiently removed, formation of capping layer on the surface of RGO, and good dispersion of RGO in aqueous solution. Furthermore, biomolecules were identified by Gas Chromatography-Mass Spectrometer (GC-MS), where eucalyptols, aldehydes, terpineols, alcohols, amides and ethers of Eucalyptus leaf extract may act as reducing and capping agents for the formation of RGO. Finally, the methyl blue (MB) adsorption on EL-RGO, activated carbon, graphite powder and commercial graphene were investigated separately. The order of the maximum adsorption capacity of different adsorbents emerged as: EL-RGO > commercial graphene > activated carbon > graphite powder.

Effect of microencapsulated Jabuticaba (Myrciaria cauliflora) extract on quality and storage stability of mortadella sausage.

The aim of the present study was to add microencapsulated Jabuticaba aqueous extract (MJE) to mortadella as a natural dye and to evaluate its possible antioxidant and antimicrobial activity during refrigeration. Anthocyanins in the extract were quantified and identified. Three treatments of mortadella were prepared: without dye (Control), with cochineal carmine (Carmine) and with the addition of 2% MJE. We determined the chemical composition of mortadella, along with pH, instrumental color, lipid oxidation, microbiological characteristics (Escherichia coli, Staphylococcus aureus, Salmonella, sulphite-reducing Clostridium, aerobic mesophiles, aerobic psychrotrophics and lactic acid bacteria) and sensory acceptance during storage at 4 °C for 56 days. MJE showed high content of anthocyanins, with prevalence of cyanidin-3-glucoside. MJE improved sensory acceptance of texture and flavor of mortadella (P < 0.05), but we observed a slight decrease in color and aroma attributes (P < 0.05). Lipid oxidation of mortadella was not influenced by MJE or cochineal carmine. MJE also displayed a minor effect on physicochemical and microbiological characteristics during storage. As MJE did not alter most of mortadella sausage's evaluated characteristics, it could be used as a natural dye in order to make better use of agro industry waste and to create a meat product enriched with natural antioxidants.

Novel laccase-like multicopper oxidases from the Myrothecium roridum fungus - production enhancement, identification and application in the dye removal process.

The aim of this study was to overproduce, identify and apply novel laccase-like multicopper oxidases (LMCOs) from Myrothecium roridum in a dye removal process. LMCOs' production was enhanced by modifying the medium and adding copper ions. After purification, two proteins, LMCO1 and LMCO2, with molecular masses of 46.7 and 66.3 kDa were discovered. Peptide analysis by mass spectrometry revealed that they belong to the cupredoxin superfamily. Characteristic peptide sequences were obtained for MCOs and bilirubin oxidases. Crude enzymes were applied in a dye decolorization process. Supplementation with 1 mM of vanillin allowed an almost complete elimination of the Indigo carmine within 3 hours. The dye was removed from a solution containing metals, surfactants and organic solvents. The in-gel assessment of the activity and decolorization ability of MCOs, followed by protein extraction and SDS-PAGE, confirmed that only LMCO2 was responsible for the dye removal. MCOs produced by Myrothecium sp. have been poorly studied before. The obtained results broaden knowledge on this subject and may contribute to the development of an eco-friendly method of dye elimination.